One suite of thick gypsum and halite layers was discovered to occur in the PaleogeneNeogene strata, Kuqa basin, Xinjiang. Exploration and study results show that sylvite deposits developed at the depth of 5100 m in the southern margin of Baicheng depression during Paleogene. Several samples of saline spring waters from the Kuqa basin were analyzed in 2015~2016. The results indicate that seven samples have higher total dissolved solution (TDS) (117.7 to 299.4 g/L) and distinctly enriched in K+ (from 15.25 to 45.68 g/L), which is several tens of time more than previous reported data (<1.0 g/L). High K+ concentrations in the spring waters are the first report in the Kuqa Basin at present. The hydrochemical classification indicates that these spring waters are dominantly chloridetype waters and belong to Ca- Cl spring brines. The ratios of hydrochemical characteristics (such as K×103/Cl, nNa/nCl, nMg/nCl, Br×10 3/Cl and nK/nBr) of potassium- rich spring waters show that they have high K×10 3/Cl and nK/nBr, low nMg/nCl and Br×10 3/Cl, and nCl-=nNa++nK+. Meanwhile, these potassium- rich spring waters are also plotted into sylvite phases area in Na+, K+, Mg2+//Cl-, SO2- 4- H2O quinary metastable phase diagram of salt- water system at 25℃. These comparisons imply that these spring waters might leach sylvite from deep strata, and discharged and seeped along fault zones under strong tectonic compression circumstance. The discovery of these potassium- rich spring waters in the Kuqa Basin, Xinjiang demonstrates that potash deposits exist in the saltbearing strata, and has important implications for exploration of potash deposits in this region.